Create insertion_in_a_linked_list.cpp

insertion_in_a_linked_list.cpp

@@ -0,0 +1,103 @@
+#include<stdio.h>
+#include<stdlib.h>
+
+struct Node
+{
+    int data;
+    struct Node * next;
+};
+
+void linkedListTraversal(struct Node *ptr)
+{
+    while(ptr != NULL){
+        printf("Element: %d\n", ptr->data);
+        ptr = ptr->next;
+    }
+}
+
+struct Node * insertAtFirst(struct Node *head, int data){
+    struct Node * ptr = (struct Node *)malloc(sizeof(struct Node));
+    ptr->next = head;
+    ptr->data = data;
+    return ptr;
+}
+
+struct Node * insertAfterNode(struct Node *head, struct Node * prevNode, int data){
+    struct Node * ptr = (struct Node *)malloc(sizeof(struct Node));
+    ptr->data = data;
+    ptr->next = prevNode->next; 
+    prevNode->next = ptr;
+    return head;
+}
+
+struct Node * insertAtIndex(struct Node *head, int data, int index){
+    struct Node * ptr = (struct Node *)malloc(sizeof(struct Node));
+    struct Node * p = head;
+    int i = 0;
+
+    while (i != index-1)
+    {
+        p = p->next;
+        i++;
+    }
+    ptr->data = data;
+    ptr->next = p->next;
+    p->next = ptr;
+    return head;
+}
+
+struct Node * insertAtEnd(struct Node * head, int data){
+    struct Node * ptr = (struct Node *)malloc(sizeof(struct Node));
+    ptr->data = data;
+    struct Node * p = head;
+
+    while (p->next != NULL)
+    {
+        p = p->next;
+    }
+    p->next = ptr;
+    ptr->next = NULL;
+    return head;
+}
+
+
+
+int main(){
+    struct Node *head;
+    struct Node *second;
+    struct Node *third;
+    struct Node *fourth;
+
+    // Allocate memory for nodes in the linkedlist.
+    head = (struct Node*)malloc(sizeof(struct Node));
+    second = (struct Node*)malloc(sizeof(struct Node));
+    third = (struct Node*)malloc(sizeof(struct Node));
+    fourth = (struct Node*)malloc(sizeof(struct Node));
+
+    // Link first and second nodes
+    head->data = 7;
+    head->next = second;
+
+    // Link second and third nodes
+    second->data = 11;
+    second->next = third;
+
+    // Link third and fourth nodes
+    third->data = 41;
+    third->next = fourth;
+
+    // Terminate the list at the third node
+    fourth->data = 66;
+    fourth->next = NULL;
+
+    printf("Linked List before insertion\n");
+    linkedListTraversal(head);
+    printf("\n");
+    printf("Linked List after insertion\n");
+    // head = insertAtFirst(head, 56);
+    // head = insertAtIndex(head, 56, 2);
+    head = insertAtEnd(head, 56);
+    // head = insertAfterNode(head, second, 45);
+    linkedListTraversal(head);
+    return 0;
+}